Mid-Atlantic Antique Radio Club - MAARC

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Mid-Atlantic Antique Radio Club - MAARC

The Mid-Atlantic Antique Radio Club (MAARC) is a hobby club for those dedicated to collecting, restoring, and preserving vintage electronics. Join MAARC!

MAARC is a club for those dedicated to collecting, restoring, and preserving vintage electronics, including radio, television, hi-fi, vacuum tube, electronic test equipment, tube audio, and yes, vintage computers and computer games. Collecting antique radio, television, hi-fi audio/stereo, electronic instruments, and test equipment is a fun and interesting pastime that appeals to a variety of folk

s. Members include pure collectors who are looking for their next great find, technicians and tinkerers who like to restore the electronics or refinish cabinets, historians and preservationists interested in the history of the technology, and those who are into it as a small business. Many involved dabble in several of these areas. All enjoy the camaraderie of a shared interest. You will find vintage electronics collectors to be a friendly and honest group who do not take themselves too seriously, while recognizing they are preserving a part of our heritage. How Will MAARC Benefit Me? MAARC meetings and our Radio Age journal provide presentations and articles covering all aspects of our interests in vintage electronics. This covers everything from repair techniques, to cabinet refinishing, to test equipment, to tube collecting, to electronics history. Looking for a little fun? MAARC members enjoy hanging out with techies who share similar interests and pas-sions. We hold a banquet and restored equipment contest at our annual RadioActiv-ity event. MAARC Offers You the Opportunity to Buy or Sell Vintage Electronics. All MAARC meetings feature a flea market tailgating period and an auction. Both provide the opportunity to buy and sell old radios, hi-fi audio, ham equipment, tubes, vintage electronics parts, service equipment, and literature at good prices. Monthly meeting tailgate sales are without any fees. Auction buyers pay no fees, while sellers pay just a small commission. Of course, there is no guarantee that all items will sell, though most do. The monthly auctions tend to be more informal, with no minimum bids and often, no reserves. Because of the prices typically realized, the monthly auctions tend to be good opportunities to buy and sell lesser quality items and parts. Twice a year we offer larger meets with bigger flea markets and auctions. These larger auctions have higher quality offerings and are more likely to garner better prices. They may have minimum opening bids, consignment limits, and other policy requirements to help manage the auction. These two events, RadioActivity and RadioFallFest, are normally in June and October respectively. Guests are invited to our monthly 3rd Sunday meetings in Davidsonville, MD (Feb, Mar, May, Jul, Aug, Sep, & Nov) or Centreville, VA (Apr & Dec). Tailgate sales for these events start at 11:00 AM, with the meeting, including a Show and Tell and a topical presentation at 1:00 PM. This is followed by an auction of a wide variety of vintage electronics. Our October Fallfest in Davidsonville kicks off at 7:00 AM with a huge auction at noon. Other events include our January Winterfest at the National Electronics Museum (NEM) in Linthicum, MD near BWI airport, and our 3-day RadioActivity event held in June at a conference facility within the DC/Baltimore region. MAARC members receive monthly issues of our vintage electronics journal Radio Age (containing interesting and in¬formative articles), on-line access to past MAARC Newsletter and Radio Age copies and to the club's members-only Internet discussion forum. If you are a member of either NEM or the National Capital Radio & Television Museum (NCRTV), you get a onetime first year MAARC dues discount ($20 vs. $24). MAARC created NCRTV, which offers photocopies of service literature at low cost (see NCRTV.org.) For additional information, visit our website:
WWW.MAARC.ORG

07/26/2025

Here is an interesting post applicable to anyone who wants a super fine finish on their restored vintage electronic device. Written by MAARC member Gordon Simonds, it is entitled "Cabinet Refinishing - The Old-Fashioned Way." Initially published in the January 1990 MAARC Newsletter, it is equally applicable to items finished in varnish, lacquer, or enamel.

"As a neophyte woodworker, I have always admired the finish of the expensive console radios of the late 20s and early 30s. In an attempt to find out how the deep, clear, glass smooth finishes were applied, I spent several days at the library researching the subject. I came across more than a few "how to" articles which purported to be "the way," but in the end I settled on this one (described in "Radio Cabinet Materials and Construction," Radio Magazine, November 1930):

"In order to secure a good piece of work, it is absolutely necessary that the woodwork be made perfectly smooth with fine sandpaper before starting. Then: (1) fill with best grade of filler; (2) if color is required, color with filler or with stain after filler is applied; (3) apply a thin coat of best shellac. After dry and hard, smooth with fine sandpaper; (4) apply three coats of best varnish, allowing each coat to dry for at least two days; (5) when dry, rub down each coat of varnish until a very smooth surface is obtained, with pumice-stone and felt, allowing one more day to dry after each rubdown; (6) final rubdown with roller stone, and for extra fine finish rub only with palm of hand; (7) clean entire surface with equal mixture of raw linseed oil and turpentine, then rub down with cheesecloth.

The process is approximately the same for enamel and lacquer, as for varnish. In inferior work, saving in labor starts with omitting to work the filler well into the pores of the wood, or in not rubbing superfluous varnish (or lacquer or enamel) away after each coat, but in putting most of the labor on the last coat only."

To the above, I would like to add the following notes:

- the final smoothing before application of filler is best done with a cabinet scraper

- sanding sealer can be used in place of shellac to seal the filled surface

- for the "roller stone" mentioned in the method above, I use rottenstone

- for rubbing down with pumice and rottenstone (both of which are readily available as powders) cut up an old felt hat into pieces the size of regular sandpaper, and use with a regular sanding block - I get my felt hats at church rummage sales

- pumice and rottenstone are used with water, and are excellent abrasives. Be sure to clean up well (with water) after rubbing

- use only the best quality gloss varnish. Beware of the so-called "satin" varnishes on the market. They contain opaque material which hides the wood grain (and hence defeats the whole process). You can get any level of gloss you like by rubbing the last coat with pumice-stone to cut all gloss, and then using rottenstone to bring up the desired level

- varnish will not dry properly in conditions of high humidity. Also, beware of dust!

- I haven't found any easy way to "rub" carved areas - so far I use Q-tips.

The procedure described above takes a lot of elbow grease and about two weeks to complete. I realize that it isn't for everyone, but for that special set the results justify the effort."

So we fast forward 35 years to today. Using the Lowes app on my phone, here is what found:

Most 'wood filler' is for filling gouges, but they still carry a 'grain filler' called Aqua Coat. This Water Based grain filler helps achieve a glass smooth finish on hard to fill woods. It penetrates and seals the pores minimizing the absorption of your topcoat, achieving a glass smooth finish. It is compatible with oil-based and water based primers, lacquers and paints, and minimizes the absorption of your topcoat, which leads to less coats of paint or lacquer needed saving you time and money.

Lowes still carries stains, shellac, oil-based varnishes, linseed oil, and turpentine. They only carry lacquer paint in spray cans, but you can still buy brush applied oil-based enamel paint.

Lowes doesn't carry pumice, roller stone, or rottenstone, but Amazon offers pumice stone and rottenstone powder (they carry Mohawk products), as well as felt blocks.

Do you have a method for fine-finishing your restored vintage electronics? Let's hear it.

07/25/2025

Here is an article that addresses line cord replacement. It was written by long-time MAARC member Jay Forbes, who runs a commercial vintage electronics repair service. Jay ran his business out of Ashburn, VA for many years, does excellent service work, and is always willing to share his knowledge. He now lives in and runs his business out of his home in Georgia. You can find his service listed on the MAARC website Interesting Links page. Here is the link: https://maarc.org/radios/

This Service Note article, entitled "RESISTANCE LINE CORD REPLACEMENT CIRCUIT," comes from the February 1990 MAARC Newsletter. It offers a simple solution for an otherwise dangerous design flaw.

"Early series-filament tube radios employed resistance line cords to drop the line voltage to a level such that the tubes' heater string voltages plus the line cord's voltage drop summed to a nominal 120 volts. Typical line cord ratings ranged from 150 to 180 ohms at approximately 30 watts.

Resistance line cords are dangerous for two reasons: there is a fire hazard due to possible overheating, and the utilization of asbestos for the resistance wire insulation. For these reasons, I always replace the resistance line cord with a regular line cord plus the following circuit (Fig. 1 - see photo) mounted underneath the chassis. Reconfiguration of existing chassis wiring may be necessary to incorporate this circuit. (Note, depending on the vacuum tubes used in the series string, adjust the component values in accordance with Table 1 - see photo. Also note that the resistor is not used if the radio has no pilot light.)

The diode in Fig. 1 replaces the resistance line cord by cutting line voltage in half through rectification of the ac sine wave. Increasing values for capacitor C (in accordance with Table 1 - see photo) raise the filtered voltage supplied to the heater string."

Jay went on to say that a new resistance line cord replacement product was available from Antique Electronic Supply in Arizona. It delivered 0.25 amperes (tubes' rated filament current) to the heater string, but that sometimes such devices can generate noise adversely affecting the performance of the radio. I don't see such a product still being offered by Antique Electronic Supply.

Does anyone have an alternate solution for the replacement of the resistance line cords of early string series radios? Let's hear it.

07/24/2025

Today's post comes from long time MAARC member Robert Lozier. Robert has made some excellent presentations for MAARC, and always brings a superb item as an entrant into our Old Equipment Contests. This post comes from the November 1989 MAARC Newsletter, and is entitled "A PRIMER ON HOW TO PREPARE OLD RADIO EQUIPMENT FOR EXHIBITION." Although somewhat dated, the guidance still applies.

"Most of us do not have the time and means to travel about the country to see private collections. Our best chance to see the old gear is at exhibits sponsored by the various radio clubs. All too often, however, we see the equipment placed with no information at all as to why it might be on display. There is really no excuse for not presenting at least some information on the item that is on exhibit. This article is intended to give you a better understanding of how you can go about preparing an equipment display. It is not intended to be "the last word" on the subject but more of a primer from which you can better develop your own ideas.

1. Types of information that can be presented in the display.

At the very least, you should be able to trace out the circuit of the set and produce a schematic. If the circuit is very complex, at least a block diagram with notations about special circuit features should be presented. Spend some time thinking about why the engineers and marketing people might have decided to build this product in the first place or why the public would have demanded such a product. You do not have to know for certain why the item is built in the way it is... Just identify your statements as theory presented in order to stimulate thought on the subject.

It's always great to tie an item into stories about the people and facilities where the product was built and the people that used the product originally. In addition to technical design considerations, you should give some thought to the aesthetics or utility of the packaging of the equipment.

Most of us do not have access to great libraries of technical information; but collectively, your fellow amateur communications historians own a huge variety
of documentation. You can reach many of them by advertising for information in the various newsletters. You can also obtain permission to include copies of articles that have been printed in the Old Timer's Bulletin, which was the original name of the quarterly journal published by the Antique Wireless Association (AWA OTB), RADIO AGE, etc. While your local library may not have microfilm libraries of technical magazines like RADIO NEWS and QST; they will often have files of popular magazines such as LIFE, SATURDAY EVENING POST, etc. In these magazines you can find many advertisements for the more popular brands of radio receivers.

2. How to prepare this information for use in a display.

Almost everyone knows someone that can use a 35mm camera equipped with a close-up lens. Use it to photograph details of the set that cannot be seen while the set is on display. Or use the photos to highlight features of construction.

Go to your local office supply store and get small stick-on colored arrows to apply to the photos. Apply a number to each arrow and then show notes below the photo. These photos should be large enough so that they can be viewed in less than ideal lighting conditions -- at least 4" x 6". (While at the store, take some extra time to look around, you will find many items that could help you to make a better looking display).

When mounting text on a display, remember that normal size printing from a typewriter (12 point) is not easy to read in an exhibit environment where you may have to stand at a distance of three or four feet from the mounting surface. Use text that is about 140% larger (16 to 18 point). In the BODY of your text, do not use all capital letters and do not use highly stylized type fonts such as Script or Old English.

Also make use of double enlargements (say 24 point font) to create headlines for your text. And there are all sorts of dry transfer letters available for this purpose. Take the time to frame the text that you plan to mount to your display with a colored background paper. Example: If your sheet of text is 8" x 10" then center it on top of a sheet of colored construction paper that is 8 1/2" x 10 1/2".

Keep in mind that it is possible to have a display that acquires a cluttered appearance. It is sometimes possible that you may have more copies of articles, advertisements, etc. than can fit easily. Place this supplementary information in a note book. Use page protectors to insure durability.

If there is a great deal of information on the item then you should offer a summary of main themes for the display in a central panel. Otherwise, you stand to lose the casual viewer before you can 'hook' him on the subject.

3. Now comes the time to consider the construction of the display support.

Always assume that you will have nothing but a bare table top, no walls around on which to mount things AND that table space will be VERY LIMITED. One of the easiest display supports to make is shown in the illustration. Don't worry if you live in an apartment and own no tools for making such a display support. Almost all towns have some sort of senior citizens center and many of them feature a woodworking shop with all the people and equipment that are necessary. It should be possible to find someone there that would be eager to cut up and assemble the material for you. The materials for this display are cheap and can be found at your local home improvement center. A 4' x 8' sheet of 1/8th inch thick - gloss white - pre-finished hardboard will cost $10 to $13 and will provide enough material for two or three displays... Don't worry that you don't have a truck or van to bring it home ... Just ask to have the sheet ripped into two or three pieces before you leave. One half inch by one inch clear spruce, fir or pine lumber is used to re-enforce the hardboard and prevent warping. It is usually found in their section of 'specialty lumber' or 'moldings'. Fifteen feet of 1/2" x 1" to make one display should cost you less than $5.00. A set of four 1" brass 'broad hinges' will cost about $3.00.

Be sure to take the time to use a router to round the edges of the boards. Little things like this make your display look so much more professional. It only takes a few minutes longer ....

When the hardboard is cut to size, there will be some chipping of the white coating. If the chips are kept small then all that is necessary to make the edges look good is to round them off using a sheet of sandpaper glued to a block of wood.

Use ordinary white or yellow carpenters glue to fasten the 1/2" x 1" lumber to the display. Hot melt glue does not adhere very well to the hardboard. The sanded edges of the hardboard will have a dull - light brown color. The display will look much better if you use a dark brown or black stain or flat paint to darken this edge. Use the same coating on the back of the hardboard and on the lumber used as re-enforcements to the hardboard.

When installing the hinges, be sure to allow enough space between the panels for the materials that are to be mounted permanently to the hardboard panels. Otherwise these hinges will be under a great deal of tension when you close the panels of the display.

4. Setting up the display.

Always bring a white or light colored (with no pattern) table cloth for use under your display. I have had to set up in exhibit areas where there were no table cloths available or they were crimson red in color... It is 0K to make use of an old fashioned table scarf as shown in the photo but if you do this, you should place the principal component of the display on a light colored platform to visually isolate the item from the pattern of the table scarf. This platform is only a sheet of the hardboard glued to a base piece of 3/4" thick pine shelving. Make the hardboard overlap the base piece about 1/2" on all edges.

Consider leaving a small stack of your calling cards with your display. It is always possible that someone that views your display will have some additional information that they will share with you.

5. Conclusion

The whole purpose of making up a display for your equipment is not so much to 'put on a slick show' but rather to create an environment in which your item will be displayed to best advantage and make it a great deal easier for the display viewer to learn something about your item. And .... it can be fun and very satisfying to assemble a display like this ! ! !"

Good advice, no? Here are my two cents on this subject. Need a schematic? Do a Google search on the make and model of your item. Odds are very good you will find the schematic. Some sources are free, while others sources may charge you for a download. Rider's Perpetual Troubleshooter's Manual, Vol 1-23 is available online through the Internet Archive. The entire set, including the index, covering radios from 1930 through 1952 can be accessed and downloaded for free. Here is the link: https://archive.org/details/riders_202008/Index%2001-15/

Beitman's Most Often Needed Radio Diagrams and Servicing Information 1926-1969 are also available on the Internet Archive at this link: https://archive.org/details/BeitmansMostNeededRadioDiagrams/1926-38/

Sam's Photofax schematics, covering all kinds of newer (1940's through 1970's) vintage electronics equipment, can be found online as well. Other good sources for free schematics include the Boat Anchor Manual Archive (https://bama.edebris.com/manuals/) and the RadioMuseum (https://www.radiomuseum.org/).

MAARC members can access the "Radio Brochure Compendium" on the Members Only section of the MAARC.ORG website to find advertisements related to their radio. The Internet can also provide you access to publications like RADIO NEWS, QST, LIFE, SATURDAY EVENING POST, etc.

Office supply stores now offer folding foam panels that make great display props, as illustrated in the attached photo. You can even get these at Dollar General stores. If you are willing to spend some money, you can create a PowerPoint of the display you want to use with your item and have it printed on a large foam at an office supply or shipping supply (like UPS or FedEx) store.

BTW, the other photo shows Robert with his blue ribbon entree for this years Old Equipment Contest. Thank you Robert for your excellent article and continued support of MAARC.

Do you have any other display suggestions? Let's hear them.

07/23/2025

Today is catchup time.

On July 17th we posted about WWV. MAARC Facebook follower John C. Wise passed on this tidbit: Does any know that the Atomic Clocks (I have one)? It receives its time update via a 60 kHz digital VLF transmission from the same Fort Collins, CO site known as WWVB. Thanks for sharing John.

On July 18th we posted an article on "Collecting Philosophies" with an emphasis on the sharing of knowledge. John Wise agreed with the article. "That's me, more of an electronics historian than just collecting old stuff." I like old radios for the technology and unique circuit designs that were was used historically in the time era in which it was made. "We get satisfaction getting the old electronics working like new again. And I like sharing what we know.

I'm not all that proficient at restoring cabinets and cases. The electronics of the sets are more important to me than the perfect or unique looks on the outside. I find most of the unique looking sets have mediocre electronic circuits and usually I'm not interested in collecting them. I do enjoy old tube radios, older transistor radios, HiFi/stereos, tape machines, test equipment and all kinds of electronic parts. You could say we're a collector of electronic things."

My two cents on 'unique looking sets with mediocre electronic circuits.' Look at the highly collectable Sparton radio sets like the Nocturne, Sleigh, and Bluebird with their unique mirrored glass design, and the Cloisonne, all having that Art Deco style and craftsmanship. Their cases are 'totally tubular', but their radio electronics were nothing special at all.

Long time MAARC member Randy Warren had this to share on collectables: "If the collectible has little to no value, it will vanish from the market, value provides a motive to keep a thing rather than tossing it out. Value also separates the trash from the treasure, allowing enjoyment for the innovations of the collectible vs. the common item. And while it would be great if we all could get a Marantz 8B for a couple of dollars, the recognition of its quality is such that its value due to its construction and quality of parts, etc. insure that it will remain unmolested compared to say, a Dynaco ST-70, which are common and often found in a molested state, ruining any aspect of its learned construction. Of course, we can learn from crappy stuff what not to buy/build/collect, etc.

A friend of mine's mother was a painter. Needless to say, her art was not up to the quality of a Monet, and had little collector value and really not worth saving. This is true of 99% of art, so there you go. The market can help eliminate the crap in everyday life and have the truly good stuff noted and admired." Thanks John and Randy for sharing.

On July 19th we posted pictures from our RadioActivity 2025 Vintage Electronics Expo. "My Bad" for not crediting long time MAARC member and "Radio Age" editor Domi Sanchez for taking and sharing those photos. MAARC member Robert Lozier shared "Always appreciate you volunteers going the extra mile to pull-off an event like this year after year. I came up from NC fully expecting a miserable hot Friday, but the weather was just about perfect. Hope somebody found a way to store some of it for next year." Robert, you wouldn't believe how many flim-flam charlatans, swindlers, or con artists we had to interview before we could find one that assured us Friday's weather would be perfect, but they missed the mark on Thursday when we had that line of thunderstorms rip though. MAARC member Stan Rosenstein also commented: "Thanks for the photos-very enjoyable to take in the vendor radio exhibit, flea market tables, meeting & greeting old friends!"

Finally, Honorable Mention to Ed Lyon and Stan Modjesky for their responses to Sunday's Electronic Sticklers quiz.

07/22/2025

Here is a topic many may not be familiar with. It comes from the November 1989 edition of the MAARC Newsletter. Written by Gordon Symonds, it is entitled "The Use of Radioactive Isotopes in Electron Tubes."

Radioactive isotopes have been used in the manufacture of radio tubes since the 1920s, when minute quantities of Thorium were used to improve the emission characteristics of tungsten cathodes. In later years, other radioactive materials were employed to improve the operating characteristics of other tube types, such as voltage regulators.

The use of some isotopes to improved performance is something of a mixed blessing. All radioactive elements can be described in terms of their "half-life", which is the length of time required for the radioactive activity (measured in Curies) to be reduced to half of its former value. This is not a problem for most tubes, but can be important for those using the Cobalt 60 isotope. To paraphrase Douglas MacArthur "old 0B2s never die, they just fade away."

Following is a partial list of tubes using isotopes:
Tube Type Isotope Activity ( microcuries) Half-life (years)
OA2/0B2 Cobalt 60 .0067 5
1B24 Radium 226 2.0 1600
346B/376B Radium 226 1.0 1600
5589 Radium 226 1.0 1600
5790/5791 Cobalt 60 1.0 5
WL-5939 Radium 226 2.0 1600
6141 Radium 226 0.1 1600
WL-6270/6376 Radium 226 2.0 1600
6626/6627 Nickel 63 0.05 92

From the health hazard point of view, problems would arise only if the tube were broken and the isotope ingested or inhaled. In this case, Radium is the worst offender, as it is an alpha particle emitter, and induces bone cancer. The maximum "safe" level of Radium contamination is 0.1 microcurie for the whole body. For comparison purposes, that is approximately the amount of radioactivity contained in a smoke detector. Another common household item which can be used for comparison purposes is lantern mantels (of the "Coleman" type) - one of these contains the maximum body dose of Thorium (an alpha emitter like Radium).

07/21/2025

Time for the "Electronic Sticklers" answers from the April 1959 edition of "Popular Electronics". "These are fairly basic circuit analysis problems that often can be solved by inspection, but sometimes a pencil and paper are necessary. Re-drawing the circuit in a different configuration to make the connections more obvious often helps when solving total resistance, capacitance, inductance, etc., as in question #1. In this case, though, you need to be able to recognize a common configuration to be able to simplify the circuit; otherwise, you'll be writing and solving mesh equations. #2 has a simple answer and a more elaborate possibility. #3 and #4 are simple inspection problems." The attached photo lists Sticklers #1 through #4 in order.

1) Harvey Matrix discovered this network covered with solder, in his junk box. Rather than trust his ancient ohmmeter, he tried unsuccessfully to compute the resistance mathematically. Show Harvey you are slicker and quicker by solving the problem in one minute.

--Dennis Wroblewski

1. Two ohms. Redraw the network schematic in the form of a bridge circuit. You will find that the resistance values of the bridge legs result in a balanced bridge. Hence the 3-ohm resistor is an inactive component and can be omitted from the circuit. All that remains are two series resistance circuits in parallel.

2) Joe Whatsit had a black box with only two terminals showing . To find out what was in the box, Joe connected a 1 1/2-volt dry cell to the two terminals and noted the current flow. He then connected a second identical dry cell in series with the first cell and repeated the experiment. The same current was noted. With this information, Joe figured out what was in the box. Can you?

--David Borenstein

2. A short circuit. The current remains the same since the two dry cells provide not only twice the voltage but also twice the internal resistance. (Kirt note: It could also contain a constant current circuit)

3) Mr. Pennypincher, in order to save money on batteries for his portable radio, built this little voltage supply to substitute for the batteries. When he plugged in the unit, he was running a risk of a blown-out component. Any idea why?

--Ronald Wilensky

3. Since there is no surge resistor, the charging current of the capacitor would pull too much current through the rectifier. Without the surge resistor (20 cents), there's a good chance the rectifier ($1.00) would burn out.

4) With the setup shown, a diode in series with a capacitor, Harold Tinkertoy applied 100 volts r.m.s. across the circuit. Then he used his vacuum-tube voltmeter to measure the peak voltage across the diode. How much did he measure? To make the problem easy, assume that a sine wave is applied to the circuit.

--Louis E. Garner, Jr.

4. About 282 volts! How come? On one half-cycle, when the diode's plate is positive, the capacitor charges to peak line voltage... or about 141 volts (1.41 multiplied by line voltage). On the next half cycle, the capacitor's voltage is in series with the peak line voltage and thus adds to it... and 141 plus 141 equals 282! This arrangement, incidentally, is basic to voltage-doubler power supply design.

Did you get them all correct? Did you get any of them correct? Did you learn something worthwhile? I did. Now I know how a voltage-doubler circuit works.

07/20/2025

It's Sunday Quiz Day. This one, entitled "Electronic Sticklers", comes from the April 1959 edition of "Popular Electronics". "These are fairly basic circuit analysis problems that often can be solved by inspection, but sometimes a pencil and paper are necessary. Re-drawing the circuit in a different configuration to make the connections more obvious often helps when solving total resistance, capacitance, inductance, etc., as in question #1. In this case, though, you need to be able to recognize a common configuration to be able to simplify the circuit; otherwise, you'll be writing and solving mesh equations. #2 has a simple answer and a more elaborate possibility. #3 and #4 are simple inspection problems." The attached photo lists Sticklers #1 through #4 in order.

1) Harvey Matrix discovered this network covered with solder, in his junk box. Rather than trust his ancient ohmmeter, he tried unsuccessfully to compute the resistance mathematically. Show Harvey you are slicker and quicker by solving the problem in one minute.

--Dennis Wroblewski

2) Joe Whatsit had a black box with only two terminals showing . To find out what was in the box, Joe connected a 1 1/2-volt dry cell to the two terminals and noted the current flow. He then connected a second identical dry cell in series with the first cell and repeated the experiment. The same current was noted. With this information, Joe figured out what was in the box. Can you?

--David Borenstein

3) Mr. Pennypincher, in order to save money on batteries for his portable radio, built this little voltage supply to substitute for the batteries. When he plugged in the unit, he was running a risk of a blown-out component. Any idea why?

--Ronald Wilensky

4) With the setup shown, a diode in series with a capacitor, Harold Tinkertoy applied 100 volts r.m.s. across the circuit. Then he used his vacuum-tube voltmeter to measure the peak voltage across the diode. How much did he measure? To make the problem easy, assume that a sine wave is applied to the circuit.

--Louis E. Garner, Jr.

Post your answer for us all to see, along with the reasoning behind your solution. Who is going to get Honorable Mention?

07/19/2025

Thought I would share some photos from last month's RadioActivity 2025 Vintage Electronics Expo. The photos include presentations, our banquet, the Old Equipment Contest, radio assessment workbench, tube exhibit, walk-around auction from our vendor tables, and the main auction.

Did you miss it? Shame on you! Join us next year.

07/18/2025

Here is a post that comes from the October 1989 MAARC Newsletter. It has the same applicability today that it did when published. Entitled "COLLECTING PHILOSOPHIES" by Gordon Symonds, it addresses a view on those who find vintage electronics interesting, with an emphasis on learning and sharing that knowledge rather than collecting. Here goes:

"As a relative newcomer to the antique radio hobby, I would like to comment on the subject of antique radio dealers as raised by Joe Koester in the August issue of the MAARC Newsletter.

"Dealers", or those whose principal motive is profit, represent to me the commercial (free enterprise?) aspect of the hobby. If we are perceived by others as being mainly concerned with the acquisition of a collection of artifacts, then we should not be surprised if the market (flea or otherwise) responds in kind. Making a buck will never go out of fashion.

As I see it, one of the problems is the very word "collector" itself, with its implication that it is the "collection" which is important. The use of the term only encourages more and more dealers with sharper and sharper elbows to demand higher and higher prices for their wares. I would like to suggest two possible actions we can all take to head off this problem. Firstly, we should make an effort to shift the emphasis from the importance of acquiring collections to the historical and technical side of radio. The acquisition of radio sets, while remaining an important facet of the hobby, should not be inappropriately emphasized. It is a matter of degree. We should actively promote the term "radio historian" and relegate "collector" to those who lust after baseball cards and other such things. This may be hard on those bitten with the acquisition bug, but in addition to saving money should result in enhanced marital harmony! Secondly, we can identify and refuse to patronize the offending individuals, except possibly in the verbal sense.

One thing that I have come to realize in the short time which I have been involved in our hobby is that there is tremendous amount of talent and knowledge out there, much of which remains unexpressed. Unless one intends to establish a permanent museum, I feel that a significant portion of the radio historians (sic) time should be spent learning about his field of interest and sharing it with others, either by writing about it in the various journals and newsletters or giving presentations at meetings. In this way, virtually anyone can make a lasting contribution to this most interesting and diverse of hobbies.

I find it somewhat ironic that this issue is being aired in the MAARC newsletter, which has always placed a heavy (and appropriate) emphasis on the preservation and promotion of the technical and historical aspects of radio and the fellowship of a truly diverse group of most interesting people. Who could ask for more?"

My personal observations are that although the prices for vintage electronics appear to be in a downward trend, their abundance (at lower prices) can cause issues with being a good steward. We should not be overstocking our basements and garages with "stuff."

This hobby has many focus avenues. Some members like antique radios and their history. Others may be into military gear. Some folks may enjoy H-Fi, or transistor radios, or test equipment, or vacuum tubes. Whatever your focus, and we can all benefit from sharing the things that we have learned in those areas of interest.

Comments? Let's hear what your thoughts are.

Address

3789 Queen Anne Bridge Road
Davidsonville, MD
21035

Website

http://www.maarc.org/

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